Fabrication of FeAl/TiC composites through reactive hot pressing

Abstract

FeAl/TiC composites were fabricated by reactive hot pressing blended elemental powders. The TiC content was varied from 50% to 80% (volume fraction) and the aluminum content in the binder phase was changed from 40% to 50% (mole fraction). The effects of these compositional changes on the densification process and mechanical properties were studied. The results show that with the increase of TiC content, densities of the composites decrease due to insufficient particle rearrangement aided by dissolution — reprecipitation reaction during hot pressing. Closely related with their porosities and defect amount, the hardness and bend strength of the composites show peak values, attaining the highest values with TiC content being 70% and 60%, respectively. Increasing the aluminum content is beneficial to the densification process. But the hardness and bend strength of the composites are reduced to some extent due to the formation of excessive oxides and thermal vacancies.

Keywords

FeAl/TiC composite / densification process / mechanical property / reactive hot pressing

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